We need it soon. The supply of Internet Protocol version 4 (IPv4) addresses is dwindling, spurring interest in the transition to IPv6, with its exponentially larger address space. Since the IPv6 standard was established in 1999, operating systems and network equipment have steadily added support, says John Curran, president and CEO of the American Registry for Internet Numbers. But the transition got started so early that it has since faded into the background.